Important: kernel

Issue Overview:

A weakness was found in the Linux kernel’s implementation of random seed data. Programs, early in the boot sequence, could use the data allocated for the seed before it was sufficiently generated. (CVE-2018-1108)

A flaw was found in the way the Linux kernel handled exceptions delivered after a stack switch operation via Mov SS or Pop SS instructions. During the stack switch operation, the processor did not deliver interrupts and exceptions, rather they are delivered once the first instruction after the stack switch is executed. An unprivileged system user could use this flaw to crash the system kernel resulting in the denial of service. (CVE-2018-8897)

A flaw was found in the Linux kernel’s implementation of 32-bit syscall interface for bridging. This allowed a privileged user to arbitrarily write to a limited range of kernel memory. (CVE-2018-1068)

The Linux kernel is vulerable to a use-after-free flaw when Transformation User configuration interface(CONFIG_XFRM_USER) compile-time configuration were enabled. This vulnerability occurs while closing a xfrm netlink socket in xfrm_dump_policy_done. A user/process could abuse this flaw to potentially escalate their privileges on a system. (CVE-2017-16939)

A flaw was found in the Linux kernel where a crash can be triggered from unprivileged userspace during core dump on a POWER system with a certain configuration. This is due to a missing processor feature check and an erroneous use of transactional memory ™ instructions in the core dump path leading to a denial of service.(CVE-2018-1091)

An address corruption flaw was discovered in the Linux kernel built with hardware breakpoint (CONFIG_HAVE_HW_BREAKPOINT) support. While modifying a h/w breakpoint via ‘modify_user_hw_breakpoint’ routine, an unprivileged user/process could use this flaw to crash the system kernel resulting in DoS OR to potentially escalate privileges on a the system.(CVE-2018-1000199)

A flaw was found in the way the Linux kernel’s KVM hypervisor handled exceptions delivered after a stack switch operation via Mov SS or Pop SS instructions. During the stack switch operation, the processor did not deliver interrupts and exceptions, rather they are delivered once the first instruction after the stack switch is executed. An unprivileged KVM guest user could use this flaw to crash the guest or, potentially, escalate their privileges in the guest.(CVE-2018-1087)

Affected Packages:

kernel

Note:

This advisory is applicable to Amazon Linux 2 (AL2) Core repository. Visit this FAQ section for the difference between AL2 Core and AL2 Extras advisories.

Issue Correction:
Run yum update kernel to update your system.

New Packages:

src:  
    kernel-4.14.42-61.37.amzn2.src  
  
x86_64:  
    kernel-4.14.42-61.37.amzn2.x86_64  
    kernel-headers-4.14.42-61.37.amzn2.x86_64  
    kernel-debuginfo-common-x86_64-4.14.42-61.37.amzn2.x86_64  
    perf-4.14.42-61.37.amzn2.x86_64  
    perf-debuginfo-4.14.42-61.37.amzn2.x86_64  
    python-perf-4.14.42-61.37.amzn2.x86_64  
    python-perf-debuginfo-4.14.42-61.37.amzn2.x86_64  
    kernel-tools-4.14.42-61.37.amzn2.x86_64  
    kernel-tools-devel-4.14.42-61.37.amzn2.x86_64  
    kernel-tools-debuginfo-4.14.42-61.37.amzn2.x86_64  
    kernel-devel-4.14.42-61.37.amzn2.x86_64  
    kernel-debuginfo-4.14.42-61.37.amzn2.x86_64  

Additional References

Red Hat: CVE-2017-16939, CVE-2018-1000199, CVE-2018-1068, CVE-2018-1087, CVE-2018-1091, CVE-2018-1108, CVE-2018-8897

Mitre: CVE-2017-16939, CVE-2018-1000199, CVE-2018-1068, CVE-2018-1087, CVE-2018-1091, CVE-2018-1108, CVE-2018-8897